Answer:
3468
Explanation:
We can make four digit number from the digits 6,4,3,8
Smallest digit for thousands is 3=3000
Smallest digit for hundreds (out of remaining 6,4,8) is 4 = 400
Smallest digit for tenths (out of remaining 6,8) is 6= 60
And unit digit is 8
So the smallest number is 3000+400+60+8=3468 answer